Beijing: A day after asking Japan to stop encroaching its territory, Chinese military on Wednesday for the first time deployed its naval ships to patrol the islands disputed with Tokyo in the East China Sea.

This is the first time in recent months China deployed its naval vessels for patrols in the islands waters replacing the marine surveillance vessels, even though some naval ships were seen in the waters earlier.

China calls the islands Diaoyu while Japan refers to them Senkakus, which were administered by Tokyo till last September after which China started challenging the Japanese hold on the islets.

Significantly they also conducted open-sea offencive and defencive training as well as exercises of intercepting and searching illegal vessels in the western Pacific Ocean on Sunday and Monday, it said.

Missile destroyer Lanzhou and missile frigate Hengshui, both from the Navy's Nanhai Fleet, entered the sea area via the Miyako Strait on Tuesday night, the report said.

Today's patrol by the Nanhai fleet ships came after vessels from the PLA Navy's Beihai Fleet and Donghai Fleet had previously patrolled the Diaoyu Islands waters.

Yesterday Chinese Defence Ministry spokesperson Yang Yujun asked Japan to stop encroaching the country's territory asserting it has the capability and determination to safeguard them. "What is important now is for Japan to stop activities that undermine China's territorial sovereignty and take actions to ensure the issue resolved," he said while release a white paper on the Chinese military. The paper named Japan as "trouble maker" while accusing US of making situation "tenser" by forging alliances in Asia.